Intake manifolds commonly deliver air to the cylinders of an engine. Other fluids are typically delivered to the cylinders of an engine by systems connected to or separate from the intake manifold, such as fuel injection systems, exhaust gas recirculation systems, positive crankcase ventilation systems and fuel tank vapor systems. The components for these various systems are commonly assembled separately from the intake manifold and individually mounted on the engine or manifold.
Separate assembly of the intake manifold and the various fluid delivery system components can entail considerable difficulty and expense due to the interdependency of the various systems. Proper alignment, tight connections and fully coordinated control systems are often critical to the optimum functioning of the various systems. Such design and manufacturing requirements can be difficult to meet when separately assembling the various system assemblies and mounting them on an engine. For similar reasons, mounting the assembled components of these various systems as separate assemblies can also require substantial effort and expense. Also, the fluid delivery systems described above typically include many relatively small and fragile components.